Why Do Clothes Shrink?

There’s no single reason clothing shrinks, but the simplest answer may be as close as the label in your favorite top. What causes your Henley’s sleeves to shrink or your jeans to feel a little tight in the waistband and thighs, when they fit just fine a few weeks ago? The culprit may be your washer and dryer—or your washing and drying habits. Shrinkage is caused by fibers changing structure; washing and drying methods can affect the structure of the fibers. Fabrics react in different ways to washing and drying methods, so each type of fabric in your wardrobe requires proper care to prevent shrinkage.

Fabrics That Shrink

Natural fibers are more susceptible to shrinkage. The most common natural fibers are:

  • Cotton
  • Wool
  • Linen
  • Leather
  • Silk

When the fabric is prepared, the fibers are stretched. Heat and water from laundering causes the fibers to return to their original shorter, curled state. Other natural textiles, like bamboo, hemp, and Tencel offer environmentally friendly, easy-care options for clothing, but they may also shrink. Pay attention to tags so you know what’s in your wardrobe.

Fabrics Less Likely to Shrink

Synthetic fabrics and blends are less likely to shrink because they require higher temperatures to change structure than natural fabrics. Examples include:

  • Polyester
  • Acrylic
  • Nylon
  • Fabric blends, including cotton/polyester and cotton/spandex
  • Tri-blends, including cotton/rayon/polyester 

Get the Facts About Fabric Shrinkage

Clothes shrink because the fibers shorten when exposed to heat, water, and agitation—and the shrinkage knows no wardrobe bounds. A wool jacket, broken-in denim, or your favorite shirt: They’re all at risk if not cared for properly. You won’t need to consider parting with your favorite outfits when you know the best practices for washing and drying your clothing.

Care for Cotton Properly to Prevent Shrinkage

The shrinkage that occurs in cotton is known as relaxation shrinkage, a phenomenon that occurs after yarn and fabrics are put under pressure and/or tension during manufacturing. Cotton is especially vulnerable to relaxation shrinkage, which most commonly happens when fibers are exposed to damp climates or they’re left in water for long periods of time. Most cotton garments will shrink during the first wash, and during subsequent washes to a lesser extent.

Shrinkage is more likely in 100 percent cotton garments than cotton blends. Look at the label: Pre-shrunk cotton means the fabric was processed to reduce shrinkage if you follow proper washing instructions. Pre-shrunk does not mean that your clothing will not shrink further, but the shrinkage will be less over the lifetime of the garment, and especially after the first washing.

Some cotton clothing, like laid-back denim jeans or rugged moleskin pants, are made to handle rough wear—but they’re still susceptible to shrinkage and wrinkles. Follow laundering instructions, even for these seemingly indestructible garments, so you can wear them for seasons to come.

To prevent cotton clothing from shrinking:

  • Choose items made in pre-shrunk cotton or a cotton blend
  • Hand wash your cotton garment or wash on a delicate cycle in cold water
  • Remove your garment from the washer as soon as possible
  • Air dry, or dry on a low heat setting for 10 to 15 minutes, and then remove the garment from the dryer promptly

Linen Clothing Shrinks, Too

Linen clothing is also affected by relaxation shrinkage. Keep your linens out of damp areas, and dry them as soon as possible after you wash them. But here’s the catch: Your linen clothing is more likely to shrink than your cotton clothing—and a loose weave usually shrinks more than a tight one.

Here’s what you can do to reduce the risk of shrinkage in linen clothing:

  • Wash linen garments in cold water on low spin settings
  • Hang or lay flat to dry
  • The dryer can help reduce wrinkles in linen clothing, but limit drying time to five or fewer minutes

Leave Laundering Silk to the Professionals

Silk can be a tricky fabric to launder because there are so many variations, including chiffon, charmeuse, and taffeta, to name just a few. Check the tags of any silk garment you own, as some silks should be dry cleaned—not washed at home. Have your delicate silks dry cleaned so you don’t have to worry about damage or shrinkage.

If your silk clothing isn’t labeled ‘dry clean only,’ follow the washing instructions on the tag. Generally, use a mild detergent and follow these steps to keep your silk from shrinking:

  • For silk clothing labeled for machine washing, use a mesh bag and the delicates cycle
  • For gentler care, hand wash silk garments using lukewarm or cold water
  • Air dry by laying flat or hanging

Keep Your Wool Out of the Washer

Wool and cashmere fibers are shingled, or jagged, and when agitated they tangle, shorten, and shrink. The felting process does this intentionally, but your favorite fisherman’s sweater or cashmere cardigan requires more gentle treatment.

Be careful when washing wool or any fabric made from animal fibers. Most modern laundry detergents contain enzymes that work to break down any biological molecules. While these work great to get rid of grass stains or grease spots, the animal hair fibers in wool are themselves made of biological molecules. Therefore, detergents break down wool a bit more with each washing. Do your research to find wool-safe detergents and follow these washing guidelines:

  • Hand wash in cold water
  • Rinse thoroughly, and avoid stretching or wringing
  • For sweaters and knits, reshape and lay flat to dry—hanging can stretch the knit
  • Woven wools such as blazers can be hung to dry
  • Never put wool in a dryer

Tip: Mild baby shampoo is a gentle replacement if you’re out of laundry detergent.

Your Jeans Will Shrink in the Wash, Too

Denim contains cotton fibers, so your jeans will shrink a bit as well. You can thank relaxation shrinkage once more for jeans that seem to shrink in the waist, thighs, or length. Follow these rules to keep your jeans fitting beautifully:

  • Buy jeans that are slightly too big—they’ll still fit after you wash them
  • Wash them in cold water
  • Dry on low to medium heat for about 15 minutes, and then remove and allow them to air dry

It may be possible to unshrink denim: Spritz with lukewarm water, tug tight areas gently while the jeans are still damp, and let them air dry. But because the fibers continue to shrink with each washing, note that this solution is only temporary.

Synthetic Fabrics and Blends Resist Shrinkage

Because washers and dryers can’t reach temperatures high enough to alter the structure of synthetic fabrics, clothing made from synthetic materials is better able to resist shrinkage and retain its shape after washing. A synthetic material doesn’t make drying on high heat okay: Wrinkles may set in, so follow the care instructions for proper drying temperature or method.

You may see fabric blends listed on your garment’s tag—common blends include 65 percent cotton and 35 percent polyester or 95 percent cotton and 5 percent spandex. Fabric blends often include a bit of stretch for comfort, can resist wrinkles, cost less, improve washability, and even prevent shrinkage. A tri-blend—most often 25 percent cotton, 25 percent rayon, and 50 percent polyester—is ultrasoft and durable, and far less likely to shrink than pure cotton fabric.

Does Hot Water Shrink Clothes?

Clothing can shrink for a number of reasons including drying temperatures and washing methods. Hot water shrinks clothes—and fades them. While warm water can contribute to shrinkage, it does so to a lesser extent than hot water. Follow the instructions on the label and choose cool or cold water to reduce shrinkage. Bonus: It saves energy and reduces carbon pollution, making cool-water washing a better option for the environment.

Ever noticed your hemline getting shorter—but your clothing getting wider—the more you wash it? Fabric shrinks differently throughout a garment due to the fabric’s warp (lengthwise) and weft (widthwise) threads—the density, count, and type of these crossed threads can affect garment shrinkage. Corduroy clothing may shrink along the length of the fabric, the waistband may seem to get smaller, and the sleeves on wool sweaters creep shorter the longer you have them.

While washing methods do play a large role, drying temperatures are the primary cause of shrinkage. High temperatures are useful for killing bacteria on fabrics, which is why dryers can get so hot. But excessive heat causes fiber tensions to release, which will change your garment’s size—and can make wrinkles set in, as well.

Tip: Set the heat lower than what’s recommended. Your clothes will thank you.

Is Dry Cleaning the Best Option?

Because the dry cleaning process doesn’t use water, clothes are less likely to shrink—but not all clothing is suitable for dry cleaning. The solvents may strip dye from the fabric, damage embellishments, or break down bonding agents. Always follow laundering instructions to avoid mishaps.

Get to know your fabrics so you can prevent shrinkage. You may want to evaluate drying temperature and washing methods the next time you start a load of laundry.

Once you get to know your materials better, you’ll get this anti-shrinkage thing down. Pay attention to your favorite outfit’s tags, and you’ll be wearing your clothing with comfort and ease for a long time to come.

4 thoughts on “Why Do Clothes Shrink?”

  1. Why does the same fabric shrink differently in different parts of the same item? For example, the legs on pajamas will shrink while the distance from the waist to the crotch seam gets longer. Or sweatshirts will get wider but shorter.

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